Refrigeration oil separation



Nov. 10, 1931. G. w. WATTS REFRIGERATION OIL SEPARATION Filed sept. 25, 1930' Patented Nov. 10, 1931 UNITED sTATEs PATENT OFFICE GEORGE w. wATTs, or WHITING, INDIANA,`AssI`GNOn To sTANDAan'OIL comm (INDIANA), OF cnrcAGo, ILLINOIS, A CORPORATION OF INDIANA nmrGEnATroN OIL sErAn'ATrON Application mea september 25, Isso. serial inl. 484522.

This invention relates to a refrigerationk system and it pertains more particularly to4 an improved method and means for separatino' oil from refrigeration gases. A

kn obtaining unusually low temperatures by means of an absorption refrigeration unit it is necessary to use compressors for boost- 'in gas from expansion pressure to a suitable absorber ressure. When this is necessary, and particularly when a reciprocating compressor is required, oil is introduced into the system. The object of this invention is to provide a system of this type .with an 'eilicient oil eliminator or entrainment arrester. v

A further object is to provide an improved type of entrainment arrester which is simple and positive in action, and which is particularly adapted for use in a refrigeration s stem. Other objects will be apparent as the detailed description of my invention proceeds.

, The invention contemplates a refrigeration system of the absorption type in which a booster compressor is used to increase the pressure of gases entering the absorber. I contemplate the removal of entrained Oil from these gases by circulating a liquid in Contact with the compressed gas in a tower, the Oil being separated from the liquid in the base of the tower. The particular structure of this tower and its peculiar relation to the other elements of the system will vbe hereinafter described.

The accompanying drawing is an elevation of my improved refrigeration system and oil' separator, parts of the apparatus being shown in section and parts being indicated diagrammatically. p

The insulated refrigerator or brine chamber 10 encloses the 'expansion coil 11, from which ammonia gases are conducted by pipe 12 to booster compressor 13, which is preferably of the reciprocating type. The gas leaving the booster compressor in pipe 1% may contain entrained oil, and unless this oil is removed it will foul the cooling coils, cause trouble in the generator, etc.

T O remove the entrained oil I provide a tower 15 with a plurality of plates 16= having up-turned annular `flanges 17, over which are placed bubble caps 18. Liquid is maintained rom plate to plate and thence to the bottom of the tower where they separate into an oil layer and aqueous layer 21 or vice versa,

depending upon whether or not the specific gravity of the oil is greater than that of the aqueous liquid. 1t' the oil is the lighter of A the two, it may be discharged from the tank through valved pipe 23 and the heavier liquid may be discharged through valved pipe 24; if the oil is the vheavier of the two, it is withdrawn from the base of the tower through valved pipe 25 and the aqueous liquid through valved pipe 26. The level of the Oil and/or aqueous liquid may be regulated by proper control of the valves in pipes 23 and 24 or pipes 25 and 26.

The liquid which is used to remove the entrained oil from the gases is preferably concentrated ammonia liquor, although nonvolatile oil or the like may be'used. In my preferred embodiment thls liquor is circuated from the bottom of tower 15 to the top thereof by means of circulating or refiux pump 27 and pi e 28. The top plate of the tower is prefera ly provided with a central chimney 29 covered by a baiie 30 and surrounded by a series of screens of iron wire, steel wool or the like for removing any fine liquid particles introduced into the gas by the bubbling action. The oil-free gases from tower 15 are introduced by pipe 31 into the base of absorber 32 which is equipped with suitable bailies or equivalent means for obtaining intimate contact between said gases and an absorbing uid, preferably weak liquor, which is introduced at the top of the absorber by pipe 33.' The weak liquor is thus convertedinto strong liquor which is withdrawn from theI base of the absorber through pipe 34 and is forced by strong liquor ump 35 through pipe 36, heat exchanger 3 and pipe 38 to analyzer 39. The analyzer is provided with suitable baiiies, bubble plates, etc. Spot shown) and it is preferabl mounted rectly over a generator 40 whc is heated by steam coils 41. The heat from steaml coil 41 drives off ammonia gas and water vapors which enter f the analyzer 39 where they interact with strong liquor from absorber 32 and rectifier 43 to increase the concentration of ammonia in the vapors going to rectifier 43, and to decrease the concentration of ammonia in the liquor returning to the generator 40. The rectier is equipped with .a cooling coil 43A and the pur ose of the rectifier is to remove any water xweak liquor orstrong liquor) which may e carried into the rectifier by gases leaving the analyzer. The liquor so removed is returned to the analyzer by pipe 44 andthe anhydrous ammonia gas is conducted by pipe 45 to condenser 46 wherein it is liquefied. After liquefaction it is conducted to anhydrous receiver 47 and it is then supplied by pipe 48` to reducing valve 49 and expansion coils 1l hereinabove described. y

The weak liquor from the base of generator 40 is conducted by pipe 50 through heat exchanger 37, pipe 51, cooler 52 and pipe 33 `to absorber 32. Gases passing through entrainment arrester 15 will pick up some moisture and carry it over through pipe 31 into absorber 32. In Aorder to replace this liquid in the circulating entrainment arrester system I provide a valved pipe 53 at the high pressure side of stron liquor pump 35 so that stron liquor ma Ile bypassed into pipe for rep acing the iquor lost by evaporaion.

I have described the operation oi my invention simultaneously with my description of the apparatus. From this description it will be seen that I have provided a novel and eiective means for removing entrained oil from gases, and particularly for removing oil from the gases of an absorption refrigeration unit. The novel co-operation of the entrainment arrester with the strong liquor circulation system adds to the effectiveness of this entrainment arrester, and the arrester in turn adds to the eiiciency of the refrigeration system. q

While-I have described a preferred embodiment of my invention in detail, it is understood that I am not limited to said details. For example, I may use any suitable refrigerant instead of ammonia; I may use any suitable gas-li uid contact apparatus in tower 15, and may modify the system in lgeneral in accordance with engineeringpractice.

I claim:

, coil, means for 1. In a refrigeration system an absorber,

an expansion coil, an entrainment arrester between said absorber and said expansion passing refrigerant. ases from saidexpansion coil through sai arrester and into said absorber, means for passing liquorifrom said absorber to said entrainment arrester, and means for contacting said liquor with said gases therein. 2. An entrainment arrester comprising a tower, means for obtaining intimate contact between a as and liquid in said tower, means for circulating a liquid through said tower, means for circulating a gas carrying entrained oil in said tower, and means for separating and separately removin liquid from the oil separated from sai ases.

3. An entrainment arrester comprising a bubble tower, means for circulating an aqueous solution through said tower, means for removing' entrained particles from gases leaving the tower, means for removing oil from the aqueous solution -leaving the tower, and means for separately removing said oil.

4. In combination, an expansion oil, a booster compressor, an entrainment arrester, an absorber, a generator, an analyzer, a condenser and a reducing valve, meansfor circulating a refrigerant through said elements in the order named, means for circulating an absorbent through said analyzer, generator and absorber countercurrentto said refrigerant, and means for circulating a liquid from the base of vsaid entrainm'ent arrester to the top thereof.

Signed this 28th day of Aug., 1930, at Whiting, in the county of Lake, State of Indiana.

GEORGE W. WATTS.

said t 

